The ethics panel approved nearly four dozen subpoenas for documents and testimony from House members, officers and aides. Its leaders said they plan to complete the inquiry in a matter of weeks, but not necessarily before the Nov. 7 congressional elections.

"Our investigation will go wherever the evidence leads us," Chairman Doc Hastings (R-Wash.) told reporters at the Capitol. The committee is evenly divided between the two parties, and Hastings and Rep. Howard L. Berman (Calif.), the top Democrat, promised to conduct an impartial investigation into the House's handling of warnings about the conduct of then-Rep. Mark Foley (R-Fla.).

The committee's inquiry will proceed in tandem with investigations by the FBI and Florida officials. Unlike those agencies, the ethics committee has no jurisdiction over Foley, who resigned last week as ABC News was publishing sexually graphic electronic messages between him and teenage former congressional pages. Hastings said his committee will focus on the "conduct of House members, officers and staff related to information concerning improper conduct involving members and current and former pages."

Democrats and some Republicans have accused Hastert and his leadership team of brushing off early indications of a problem -- including what they called an "over-friendly" e-mail that Foley sent to a Louisiana boy in 2005 -- that might have led investigators to find the explicit instant-message exchanges that had occurred in previous years. Two high-ranking House Republicans have said they told Hastert about that e-mail, and another lawmaker says he told Hastert's staff.

Kirk Fordham, Foley's former chief of staff, said this week that he repeatedly alerted Hastert's staff in 2003 to complaints that the Florida lawmaker was showing inappropriate interest in male pages, who are high-schoolers spending a semester or two working for Congress. The FBI spent more than three hours yesterday interviewing Fordham.

Some Republicans said they are most concerned about Fordham's assertions. Scott Palmer, the speaker's top aide, has denied the allegations and spent much of Wednesday night rummaging through old e-mails and files to determine whether he ever corresponded with Fordham, a source close to Hastert said. Palmer, who was described as very emotional, told Hastert that Fordham's assertions are false, the source said.

Hastert's office has been on edge. Deputy Chief of Staff Mike Stokke, who handles politics for the speaker, has offered to resign, two sources close to Hastert said, and several aides have expressed frustration that Ted Van Der Meid, the top counsel in the office, did not do a better job monitoring the Foley situation. Hastert did not accept Stokke's resignation offer, the source said.

Hastert, addressing reporters in Batavia, Ill., reasserted that he knew nothing of complaints about Foley's behavior until the day the Floridian resigned last week. The speaker rejected calls for his resignation by a handful of conservative groups, saying: "I haven't done anything wrong, obviously. And we need to come back." At the same time, he said, "We're taking responsibility, because ultimately, as someone has said in Washington before, the buck stops here."

Hastert suggested that Democrats may have known about the lewd instant messages and leaked them for partisan advantage, but he said he had no evidence.

Hastert had hoped to announce the bipartisan appointment of former FBI director Louis J. Freeh to look into ways to improve the page program, in which teenagers live in a Capitol Hill dorm and attend a special school. But when he called Minority Leader Nancy Pelosi (D-Calif.) early in the afternoon, she declined to go along with the plan.

Pelosi saw the Freeh proposal as a ploy to burnish the GOP's image, aides said. She told the speaker that investigators should examine whether existing rules and procedures were followed before the House considers new rules, the aides said.